Engine starter



M. B. JACKSON ENGINE STAR'fER Dec. 13, 1927. 1,652,361

Filed July 2 7 1925 Patented Dec. 13 1927.

UNITED STATES;

mUnsELL B. JACKSON, or TORONTO, on'rnmo, CANADA.

- ENGINE STARTER.

Application filed J'u1y 27, 19:25. seriaim'. 46,343,

This invention relatesto engine starters adapted to start internal combustion engines, and more particularly to that type in which afstarter pinion is axially moved into and out of mesh with a gear on the engine. The pinion is normally out of mesh with the gear" and when the starter is actuated, the pinion is axially ,moved, due to inertia, int0 mesh with the gear. As soon as the engine is started the speed ofthe gear and thus the pinion is increased which causes the latter to. beiaxially' movedou't of mesh with the gear. Heretofore it has been the general: practice to. provide an abutment for limiting the return movementofthe pinion-but the V shock of the latter against the abutment is so great the pinion will rebound from the abutment and thus be fed again into engagement withjthe gear. The object of'the pres: e'ntinventionistoprovide simple means to] overcomethis objectionable feature and t0 preterit any damage to the, teeth of the pini'onand gear. if they meet end to end.

l .",I -attain my objects by means of the constructions'hereinafter described and illustrated in the accompanying drawings in whic v Fig l' is aside elevation of part'o'f e hsh s; a v V s I'Fi'g. 2 a side elevation, partly in section,

ar y starter showing the pinion in its inoperative position r p f Fig. 3a side elevation showing the pinion j in its operative position; Fight: an end elevation of Fig. 1;. A

f iggf5 a cross section on the line"5'-5 in .gF g mgf. l a

gross section 011 e line 6-,6 r

\ washer TFi'g, "13 a detail in cross's'ection of the partsas shown in Fig. 5; and

Fig.'14: a" similar view showing the parts in a 'difierent position. 7

i T fl is an extended armature shaft of anelectricj motor (not shown). 7 The shaft is turned down at 1 to vform a shoulder 1 against which a washer 1 is positionedto v form an abutment adapted to engageflone end of a spring 2'. This spring is disposed on one end of-a'sleeve 3 which is 'slidably mounted on the portion 1 of the shaftand the other end'of the spring normally engages the ends of a double ortriple thread 3 formed on the sleeve. rThe latter is rotatably connected with theshaft byimea'ns of a "clutch formed of a pluralityiof projections 99% adapted to be received in recesses 4:?

formed in a collar 4. The collari's slid'ably mounted on theshaftand'is driven there with by means of arkey. A nut 5'threaded 1,652,361 PATENT OFFICE,

on the outer end of the shaft engages thecoll'arto move it and thus the sleeve 3 axspring 2. v r 1 'A pinion 6' loosely threaded on the sleeve is adapted to be axially moved into and out of mesh with a gear 'I connected with the crankshaft of an. engine (not shown), the common practice beingto secure "this gear ially on the shaft against the tension of the to the enginefly wheel. (When theshaft l is set in motion thepinion is axially moved,

due to its inertia, from its normal position,

as shown in Fig.2 2, into {mesh with the gear. hen the engine is started the speed of the gear-is increased relative to the normal speed of thepinion whereby'the pinion is'rotated relative toits shaftand is thus axially moved out of mesh with thegear. The collar at is adapted to" limit the outward movement of, the v pinion: To prevent the latter 'rebounding from the collarand re-meshing or contacting with the gear, lpro'vide the pinion with, means for 'frictionally engaging the sleeve threads. I

W Oneendof the pinion is counterbored at" 6 -toreceive a nut 8 threaded on the sleeve V3 and having'a projection 8 adapted to en gage one end of 'a curved spring9, theother end of which engages a projecting end 6 of one of the pinion teeth. The end of the tooth 6? which is adjacent the end6 is cut away to permit partial rotation of the, pro

jection 8 The counterbore' adjacent itsouterfend axial movement relative to the pinion '6. A housing 11' carried by the collar 4; is adaptedto'enclo'se the parts. The spring 9 recessed at 10, to receive the spring washer V lO adapted to engage the nut8 to limit its tends to rotate the nut andpinion relative to one another (see Figs. 5 and 13), whereby the threads SPWonthenut 8 engage the forward sides-of the threads 3 and the threads 6? on' the pinion engage the rear sides of the threads 3* to, frictionally look no I ly threaded on the sleeve which permits a limited rotary movement of the PllllOIl threads relative to the sleeve threads without moving the pinion axially of the sleeve;

When the shaft and thus the sleeve are rotated to start the engine, the threads 3 and the threads 8 are rotated relative to the threads 6, due to the inertia of the pinion, which releases the frictional engagement of these parts andpermits the plnlon tobe axially moved into mesh with the gear 7. As soonas the pinion startsto mesh with the gear, the latter prevents the pinion rotating which results in the shaft belng threaded throughit. The pinion is adapted toengage the spring 2, see Fig. 3, whichdimits its axial movement and ermits the shaft, sleeve and nut to be fart 1G1 rotated relative to the pinion until the forward sides of the threads 3 engage the threads 6 to form a drive connection between the shaft and pinion and thus rotate the gear 7. hen the engine starts the pinion 6 is rotated relative to the shaft which axially moves it out of mesh with the gear, as hereinbeforc described, and permits the spring 9 to again act on the pinion andnut to frictionally engage thethreads 3.

Should the teeth of the pinion and gear meet end to end, the axial movement of the former towards the gear will be stopped which will permit the spring 9 to rotate the pinion relative to the nut until the pinion threads 6? engage the sleeve threads 3*. As

this is a vcrvsudden engagement the pinion threads slide along the sleeve threads which causes thepinion to be axially moved away from the gear. It is thus obvious that, with the above construction therewill be no constantrubbing or grindingaction between the gear and pinion which results in their teeth being damaged,

By adjusting the collar 4, ashereinbefore described, the amount of travel of the pinion into and out of mesh with the gear maybe varied.

lVhatI claim is: I y y y 1. In a starter for use with an internal combustion engine, the vcombination of a starter shaft provided with a thread;

inion threaded on the shaft and having a imited rotary movement relative to the thread; a nut threaded on the shaft and freely carried by the pinion; and a spring tending to rotate the nut and pinionrelative to one another to frictionally lock the pinion against movement towardsthestarting position, releasebeing effected by a relative rotary movement of the shaft and pinion when the former is set in motion,

2. In a starter for use with an internal combustion englne, the combination of a starter shaft provided with a thread; a

pinion loosely threaded on the shaft; a nut threaded on the shaft and carried by the pinion; and a spring tending to rotate the nut and pinioni'elativato one another to frictionally engage the adjacent sides of their threads with the sides of the shaft thread the pinion thread bein disengaged from the slmittthread by a re ative rotary moven'icnt of the nut and pinion when the shaft is set in motion; i v p in a starter for use with an internal combustion engine, the combination of a. starter shaft provided with a. thread; a

pinion loosely threaded on the shaft, the

pinion being countcrbored at one end;fia nut starter shaft provided with athread; a pin 2 ion looselythreaded on the shaft, the inion being counter-bored at one end; anutt readf ed on the shaft ada ted to be freely mounted in the said counter ore and provided with a projection; and a curved spring havilxifione end in engagement with the piniona other end in engagement with the projee-l tion and tending to rotate the pinion rela tive to the nut, whereby the pimonandinut frictionally engage the op osite sides of-the shaftthread,the shaft w 1en setin motion being adapted to move relativeto thepinion and thus disengagethe thread o f-the "latter from the thread of the former. i i

5. In a starter for use with an internal combustion engine the combination of a starter shaft; a sleeve mountedonthefshaft and adapted to be driven thereby and provided with a thread; an abutment; a threaded on the sleeve; aispring disposed on the sleeve and having one end in engagement with the abutment and the other end no rmally in engagement with thethread onthe sleeve and adapted to engage the pinion; and means forlimiting the outward movementof the pinion adapted to be adjustedon' the shaft against the pressure of the saidspring.

(3. In a starter for use with an internal combustion engine the combination of a the a starter shaft having one endthreaded; a

normally engaging the abutment and the shaft thread and adapted to engage the pinion; and a nut threaded on the end of the shaft toadjust the collar axially of the shaft.

7 In a starter for use with an internal combustion engine having a gear'for revolving the crank shaft thereof the combination of a starter shaft provided with a plurality ofthreads; a. pinion loosely threaded on the shaft and adapted to be axially moved into and out of mesh with the gear; a nut threaded on the shaft and'carried by'the pinion;

a spring tending to rotate the nut and pinion relative to one another to cause the ad jacent sides of each of their threads'to yieldingly engage the opposite sides of a shaft thread, the shaft when set in motion being adapted to move relative to the pinion to disengage the pinion thread from the shaft thread; and an abutment adapted to engage the pinion to limit its axial movement when tween the shaft and pinion.

"8. In a starter for use with an internal combustion engine having a gear for revolving the crank shaft thereof the combination of a starter-shaft provided with a plurality of threads; a pinion loosely threaded on the and a spring tending to rotate the nut and pinion relative to one another to cause the adjacent sides of each of their threads to yieldingly engage the opposite sides' of a shaft thread; the shaft when set in motion bein adapted to move relative to the pinion to isengage the pinion thread from the shaft thread, the spring being adapted to rotate the pinion relative to the shaft thread to bring the, pinion thread suddenly into engagement with the shaft thread and thus cause the pinion to slide along the shaft thread and move axially away from the gear 7 .if the pinion does not mesh with the gear.

Signed at Toronto, Canada, this'20th day l i of July, 1925. t I MAUN SELL B. JACKSON. 

